On Thu, 18 Aug 2022 16:10:45 +0800, Jason Wang <[email protected]> wrote: > On Thu, Aug 18, 2022 at 11:04 AM Xuan Zhuo <[email protected]> wrote: > > > > Legacy virtio pci has no way to communicate a change in vq size to > > the hypervisor. If ring sizes don't match hypervisor will happily > > corrupt memory. > > > > We add a check to vring size before calling > > vp_legacy_set_queue_address(). Checking the memory range directly is a > > bit cumbersome. > > > > Signed-off-by: Xuan Zhuo <[email protected]> > > --- > > > > v2: replace BUG_ON with WARN_ON_ONCE. @Linus > > > > drivers/virtio/virtio_pci_legacy.c | 9 +++++++++ > > 1 file changed, 9 insertions(+) > > > > diff --git a/drivers/virtio/virtio_pci_legacy.c > > b/drivers/virtio/virtio_pci_legacy.c > > index 2257f1b3d8ae..091e73d74e94 100644 > > --- a/drivers/virtio/virtio_pci_legacy.c > > +++ b/drivers/virtio/virtio_pci_legacy.c > > @@ -146,6 +146,15 @@ static struct virtqueue *setup_vq(struct > > virtio_pci_device *vp_dev, > > goto out_del_vq; > > } > > > > + /* Legacy virtio pci has no way to communicate a change in vq size > > to > > + * the hypervisor. If ring sizes don't match hypervisor will happily > > + * corrupt memory. > > + */ > > + if (WARN_ON_ONCE(num != virtqueue_get_vring_size(vq))) { > > + err = -EPERM; > > + goto out_del_vq; > > + } > > I wonder if it's better to have a num_min instead.
num_min? What is that? Thanks. > > Thanks > > > + > > /* activate the queue */ > > vp_legacy_set_queue_address(&vp_dev->ldev, index, q_pfn); > > > > -- > > 2.31.0 > > > _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
